1. Technical Field
The present invention relates to a semiconductor package and a method of fabricating the same, and more particularly to a ball grid array (BGA) semiconductor package and a method of fabricating the same.
2. Description of the Related Art
The persistent demand for miniaturization of semiconductor products requires light, thin and small semiconductor packages as well as high integration of semiconductor chips. To meet these demands, solder ball packages such as ball grid arrays (BGAs), using solder balls as mounting units, have been developed. BGA packages include a typical BGA package, a board on chip (BoC) package and a flip chip package.
The typical BGA package has a semiconductor chip mounted on a circuit board (CB). Generally, bond pads of the semiconductor chip are electrically connected to bond fingers on the circuit board by metal wires. In the BGA package, the bond fingers may be located on the periphery of the region where the semiconductor chip is placed. Therefore, dimensional shrinkage of the circuit board and the resulting package dimension shrinkage are limited. Moreover, the metal wires are usually formed of gold, which increases the package fabrication cost.
The BoC package includes a circuit board having a window, and bond pads exposed within the window. The circuit board has bond fingers on the surface opposite that which contacts the semiconductor chip. The bond pads and the bond fingers are electrically connected to each other by metal wires. However, the window must be sufficiently wide to allow the operation of a capillary of a metal-wire bonding system used for forming the metal wire. Accordingly, the dimensional shrinkage of the circuit board and the resulting package dimension shrinkage may be limited due to the size of the window. Furthermore, similar to the typical BGA package, the metal wires are usually composed of gold, which increases the package fabrication cost.
To fabricate the flip chip package, metal projections are formed on bond pads of a semiconductor chip. Then, the semiconductor chip with the metal projections is turned upside down and bonded to a circuit board. However, the fabrication of the flip chip package has the drawback of being performed at a high temperature.
Consequently, a BGA package having reduced size and cost is desired to address these and other disadvantages of the conventional BGA packages.